g-jobbing was shut down circa 77. It was not a rare practice. I knew a fo who did 40+ after bethel service. It was do-able and became easier from the changes that released the 76 Mayflower. Seems to me that the mayflower resulted from 1975 and also from the amended contract from 4 years to 1 year; whoever wanted to leave was free to go and they did. Then work hours were shortened and Sat was only 1/2 day. Depending on where you worked though, the only risk was, so late at night, getting mugged or killed on the street or riding the subway.
I have seen old men return to the org 40 years+ after leaving, some left to go to the army, etc., then they decided to return and it took a while to be accepted back but they did it.